Process of preparing acetaldehyde from acetylene.



fla 'w -H.

PAUL DUDEN' AND GUSTAV PETERS, F HOOHST-ON-THE-MAIN, GERMANY, ASSIGNORSTO FABBWEBKE VORM. MEISTER LUCIUS & BRIINING, 0F HOCIIST ON-THE-MAIN,GERMANY, A CORPORATION OF- GERMANY.' V I PROCESS OF PREPARINGAOETALIDEHYDE FROM AOETYLENE.

mamas. No Drawing.

To all whom it may concern Be it known that we, PAUL DUDEN,Pl1.D.,"

professor of chemistry, and GUSTAV PETERS, Ph. 1)., chemist, citizens ofthe Emplre of Germany, residing at I-Iiichst-on-the-Main, Germany, haveinvented certain new and useful Improvements in the Process of.Preparing Acetaldehyde from Acetylene, of which the following is aspecification.

In the manufacture-of acetaldehyde from acetylene in presence ofsolutions containing mercury the latter gradually separates fromthesolutions in a metallic form owing to secondary reactions. Inconsequence there.-

must be effected separately, was very labor-i 'ous from-a technicalpoint; of view and entailed considerable losses of mercury. Now we havefound that the said drawbacks can be entirely avoided by-adding to theliquid of the reaction from the beginning of, the

process or in the course of it such an oxidizing agent as, on the onehand, impedes the separation of the mercury and, on theother hand, isnot able under the working-conditions employed,' to oxidize to anappreciable extent either the acetylene, or the intermediately producedmecurymompou'nds of acetylene, orthe aldehyde. 7

In our new process ferric compounds may, in the'first place, beconsidered as technically'suitable oxidizing agents. Bythe addition ofthem, the in'ecury separatiggfiin an extremely finely-subdivided form isetransformed in the nascent state into its active. salt. h The I process[can vbe;v continu- Specification of Letters Patent. Application filedJanuary 13, 1915. Serial No. 2,076. 7Q v;

This regenera- "turesin Patented Aug. 31, 1915.

ously carried on by drawing off from time to time the resultingsaturated solution of ferrous salt which is free from mercury andreturning the same into the circuit of the process after havingre-oxidized it to the ferric state, for example by atmosphericoxidation.

The following example illustrates our invention: 3 liters of sulfuricacid ofabout 6% strength and 90 grams of mercury sulfate and a smallquantity of ferric sulfate are mixed in a vessel provided with astirrer,

cooling device and a receiver, and through this mixture a strongacetylene current is passed which carries along with it theacetaldehydeproduced. At the same time a solution or a suspension offerric sulfate is run in, so that there is always an excess of theoxidizing agent in the absorption-Vessel.

The absorption remains almost constant for many hours and does notdiminish until the ferric sulfate contained in the solution is convertedentirely into ferrous sulfate. The yield of aldehyde isalmostquantitative.

Having now described our invention, what we claim is: 1. The process ofpreparing acetylene by means of a mercury compound,

in presence of sulfuric acid and an agent capable of impeding theseparation of mercury.

2. The process of preparing acetaldehyde from acetylene, w ich consistsin oxidizing acetaldehyde I from acetylene, which consists in oxidizingacetylene by means of a mercury compound,

in presence of a ferric salt.

3. The process of preparing acetaldehyde from acetylene, which consistsin oxidizing acetylene by means of a mercury compound, 1n presence offerric sulfate.

In testimony whereof, we afiix oursignar resence of two witnesses..ROFESSOR DR. PAUL DUDEN. DR. GUSTAV PETERS. .Witnesses:

- JEAN GRUND,

CARL GBUND,

